<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
    class="page-nav-bar"
    left-arrow
    title="黑马头条"
    @click-left="$router.back()"
    ></van-nav-bar>

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="loading">
        <van-loading color="#3296fa" vertical>加载中</van-loading>
      </div>

      <!-- 加载完成-文章详情 -->
      <div class="article-detail" v-else-if="article.title">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ article.title }}</h1>

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            :src="article.aut_photo"
          />
          <div slot="title" class="user-name">{{ article.aut_name }}</div>
          <div slot="label" class="publish-date">
            {{ article.pubdate | relativeTime }}
          </div>
          <follow-user v-model="article.is_followed" :userId="article.aut_id" />
        </van-cell>

        <!-- 文章内容 -->
        <div
          ref="article-content"
          class="article-content"
          v-html="article.content"
        ></div>
        <van-divider>正文结束</van-divider>
        <!--@onload-success="totalCommentCount = $event.total_count"接收子组件的
        data.data的值再点出total_count，赋值给totalCommentCount显示总评论数
  -->
        <comment-list
          :source="article.art_id"
          @onload-success="totalCommentCount = $event.total_count"
          :list="commentList"
          @reply-click="onReplyClick"
        />

        <!-- 发布评论 -->
        <van-popup v-model="isPostShow" position="bottom">
          <comment-post :target="article.art_id" @post-success="onPostSucess" />
        </van-popup>

        <!-- 评论回复 -->
        <van-popup v-model="isReplyShow" position="bottom" style="height: 90%">
          <comment-reply v-if="isReplyShow" :comment="currentComment" @close="isReplyShow = false" />
        </van-popup>

        <!-- 底部区域 -->
        <div class="article-bottom">
          <van-button
            @click="isPostShow = true"
            class="comment-btn"
            type="default"
            round
            size="small"
            >写评论</van-button
          >
          <van-icon name="comment-o" :info="totalCommentCount" color="#777" />
          <collect-article
            v-model="article.is_collected"
            :acticle-id="article.art_id"
          />
          <like-article
            v-model="article.attitude"
            :acticle-id="article.art_id"
          />
          <van-icon name="share" color="#777777"></van-icon>
        </div>
      </div>
      <!-- 加载失败：404 -->
      <div class="error-wrap" v-else-if="errStatus">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap" v-else>
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button class="retry-btn" @click="loadArticle">点击重试</van-button>
      </div>
    </div>
  </div>
</template>

<script>
import { ImagePreview } from 'vant'
import { getArticleById } from '@/api/article'
import FollowUser from '@/components/follow-user/index.vue'
import CollectArticle from '@/components/collect-article/index'
import LikeArticle from '@/components/lick-article/index'
import CommentList from '../article/components/comment-list'
import CommentPost from '../article/components/comment-post'
import CommentReply from './components/comment-reply'
export default {
  name: 'ArticleIndex',
  components: {
    FollowUser,
    CollectArticle,
    LikeArticle,
    CommentList,
    CommentPost,
    CommentReply
  },
  props: {
    articleId: {
      type: [Number, String, Object],
      required: true
    }
  },
  provide: function () {
    return {
      articleId: this.articleId
    }
  },
  data () {
    return {
      article: {},
      loading: true,
      errStatus: 0,
      followLoading: false,
      totalCommentCount: 0,
      isPostShow: false,
      commentList: [],
      isReplyShow: false,
      currentComment: {} // 当前点击回复评论项
    }
  },
  created () {
    this.loadArticle()
  },
  mounted () {},
  watch: {},
  methods: {
    async loadArticle () {
      // 开启loading
      this.loading = true
      try {
        const { data } = await getArticleById(this.articleId)
        this.article = data.data
        // 模拟异步操作，等待页面加载完成
        setTimeout(() => {
          this.previewImage()
        }, 0)

        console.log(data)
      } catch (err) {
        if (err.response && err.response.status === 404) {
          this.errStatus = 404
        }
      }
      // 请求结束关闭loading
      this.loading = false
    },
    // 图片预览
    previewImage () {
      // 得到所有的 img 节点
      const articleContent = this.$refs['article-content']
      const imgs = articleContent.querySelectorAll('img')
      const images = []
      imgs.forEach((item, index) => {
        images.push(item.src)
        item.onclick = () => {
          ImagePreview({
            // 预览图片地址数组
            images: images,
            startPosition: index
          })
        }
      })
    },
    onPostSucess (data) {
      this.isPostShow = false
      this.totalCommentCount++
      this.commentList.unshift(data.new_obj)
    },
    // 回复评论
    onReplyClick (comment) {
      this.currentComment = comment
      this.isReplyShow = true
    }
  }
}
</script>

<style scoped lang="less">
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }
    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }
    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }
  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }
  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }
  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
